<template>
  <div class="goods">
    <div class="menu-wrapper" ref="menuWrapper">
      <ul>
        <li v-for="(item,key) in goods" :key="key" class="menu-item" :class="{'current':currentIndex == key}" @click="selectMenu(key,$event)">
          <span class="text border-1px">
            <span v-show="item.type > 0" class="icon" :class="classMap[item.type]"></span>{{item.name}}
          </span>
        </li>
      </ul>
    </div>
    <div class="foods-wrapper" ref="foodWrapper">
      <ul>
        <li v-for="(item,index) in goods" :key="index" class="food-list food-list-hook">
          <h1 class="title">{{item.name}}</h1>
          <ul>
            <li v-for="(i,k) in item.foods" :key="k" class="food-item border-1px">
              <div class="icon">
                <img :src="i.icon" width="57px" height="57px">
              </div>
              <div class="content">
                <h2 class="name">{{i.name}}</h2>
                <p class="desc">{{i.description}}</p>
                <div class="extra">
                  <span class="count">月售{{i.sellCount}}份</span><span>好评率{{i.rating}}%</span>
                </div>
                <div class="price">
                  <span class="now">￥{{i.price}}</span><span v-show="i.oldPrice" class="old">{{i.oldPrice}}</span>
                </div>
                <div class="cartcontrol-wrapper">
                  <cartcontrol :food='i' @add='addFood'></cartcontrol>
                </div>
              </div>
            </li>
          </ul>
        </li>
      </ul>
    </div>
    <shopcart ref="shopcart" :delivery-price='seller.deliveryPrice' :min-price='seller.minPrice' :select-foods='selectFoods'></shopcart>
  </div>
</template>

<script>
import shopcart from 'components/shopcart/shopcart.vue'
import cartcontrol from 'components/cartcontrol/cartcontrol.vue'
import BScroll from 'better-scroll'
const ERR_OK = 0
export default {
  props: {
    seller: {
      type: Object
    }
  },
  data() {
    return {
      goods: [],
      listHeight: [],
      scrollY: 0
    }
  },
  computed: {
    currentIndex() {
      for (let i = 0; i < this.listHeight.length; i++) {
        let height1 = this.listHeight[i]
        let height2 = this.listHeight[i + 1]
        if (!height2 || (this.scrollY >= height1 && this.scrollY < height2)) {
          return i
        }
      }
      return 0
    },
    selectFoods() {
      let foods = []
      this.goods.forEach(item => {
        item.foods.forEach(i => {
          if (i.count) {
            foods.push(i)
          }
        })
      })
      return foods
    }
  },
  methods: {
    _initScroll() {
      this.menuScroll = new BScroll(this.$refs.menuWrapper, {
        click: true
      })
      this.foodScroll = new BScroll(this.$refs.foodWrapper, {
        probeType: 3,
        click: true
      })
      this.foodScroll.on('scroll', (pos) => {
        this.scrollY = Math.abs(Math.round(pos.y))
      })
    },
    _calculateHeight() {
      let foodList = this.$refs.foodWrapper.getElementsByClassName('food-list-hook')
      let height = 0
      this.listHeight.push(height)
      for (let i = 0; i < foodList.length; i++) {
        let item = foodList[i]
        height += item.clientHeight
        this.listHeight.push(height)
      }
    },
    _drop(target) {
      this.$nextTick(() => { // 异步触发过度效果，同时触发2个过渡，手机端会有卡顿
        this.$refs.shopcart.drop(target)
      })
    },
    selectMenu(index, event) {
      // 新版本better-scroll已修复PC端调试点击派发2次事件
      // if (!event._constructed) {
      //   return
      // }
      // console.log(index, event)
      let foodList = this.$refs.foodWrapper.getElementsByClassName('food-list-hook')
      let el = foodList[index]
      this.foodScroll.scrollToElement(el, 300)
    },
    addFood(target) {
      this._drop(target)
    }
  },
  components: {
    shopcart,
    cartcontrol
  },
  created() {
    this.classMap = ['decrease', 'discount', 'special', 'invoice', 'guarantee']
    this.$axios.get('api/goods').then(res => {
      if (res.data.errno === ERR_OK) {
        this.goods = res.data.data
        // console.log(this.goods)
        this.$nextTick(() => {
          this._initScroll()
          this._calculateHeight()
        })
      }
    })
  }
}
</script>
<style lang='stylus'>
  @import '~common/stylus/mixin.styl'
  .goods
    display flex
    position absolute
    top 174px
    bottom 46px
    width 100%
    overflow hidden
    .menu-wrapper
      flex 0 0 80px
      width 80px
      background #f3f5f7
      .menu-item
        display table
        padding 0 12px
        height 54px
        width 56px
        line-height 14px
        &.current
          position relative
          z-index 10
          margin-top -1px
          background #ffffff
          font-weight 700
          .text
            border-none()
        .icon
          display inline-block
          vertical-align top
          width 12px
          height 12px
          margin-right 2px
          background-size 12px 12px
          background-repeat no-repeat
          &.decrease
            bg-image('decrease_3')
          &.discount
            bg-image('discount_3')
          &.guarantee
            bg-image('guarantee_3')
          &.invoice
            bg-image('invoice_3')
          &.special
            bg-image('special_3')
        .text
          display table-cell
          width 56px
          vertical-align middle
          font-size 12px
          border-1px(rgba(7,17,27,0.1))
    .foods-wrapper
      flex 1
      .title
        padding-left 14px
        height 26px
        line-height 26px
        border-left 2px solid #d9dde1
        font-size 12px
        color rgb(147,153,159)
        background #f3f5f7
      .food-item
        display flex
        margin 18px
        padding-bottom 18px
        border-1px(rgba(7,17,27,0.1))
        &:last-child
          border-none()
          margin-bottom 0
        .icon
          flex 0 0 57px
          margin-right 10px
        .content
          flex 1
          .name
            margin 2px 0 8px 0
            height 14px
            line-height 14px
            font-size 14px
            color rgb(7,17,27)
          .desc,.extra
            line-height 10px
            font-size 10px
            color rgb(147,153,159)
          .desc
            margin-bottom 8px
            line-height 12px
          .extra
            .count
              margin-right 12px
          .price
            font-weight 700
            line-height 24px
            .now
              margin-right 8px
              font-size 14px
              color rgb(240,20,20)
            .old
              text-decoration line-through
              font-size 10px
              color rgb(147,153,159)
          .cartcontrol-wrapper
            position absolute
            right 0
            bottom 12px
</style>
